Anti-roll device



June 29, 1965 amcoRMlck 3,191,476

ANTI-ROLL DEVICE Filed March 1. 1962 FLUID SUPPLY 1 INVENTOR.

M My 4110 United States Patent 3,191,476 ANTI-ROLL DEVICE James B.McCormick, La Grange, 11]., assignor, by mesne assignments, to ArnesAtornium, Inc., Billerica, Mass, a corporation of Massachusetts FiledMar. 1, 1962, Ser. No. 176,751 7 Claims. (Cl. 83-469) This inventionrelates principally to the preparation of tissue sections formicroscopic examination and, more particularly, to an improved method ofslicing such a section from a tissue specimen.

The invention also relates to a device particularly adapted to carry outthe improved method.

In order to microscopically examine an organic specimen such as, forexample, a tissue specimen obtained through a biopsy or the like, it isnecessary to prepare thin slices of the specimen, these slices beingknown as sections. The sections have a thickness range from about 2 to25 microns and are sliced from the specimen by means of a microtomeinstrument which conventionally includes a movable carrier, on which thespecimen is mounted, and a stationary knife blade disposed adjacent thepath of movement of the carrier. The carrier is reciprocated past theknife as well as advanced toward the knife, by means of a crank, and asection is sliced from the specimen by the knife during a portion of themovement of the carrier.

As the section is sliced from the specimen and moves away from thecutting edge of the knife, it frequently curls or rolls into a cylinder,a condition which renders it unsuitable for mounting in slides or thelike. While a curled section can occasionally be straightened and used,it generally breaks when an attempt is made to uncurl it because of itsthinness and consequent low strength. As a general rule, therefore, asection which has curled is unusable.

The curling of a section generally results from improper preparation ofthe specimen or improper adjustment of the instrument, but both of thesefactors are so critical that the slicing of a section in which curlingdoes not occur generally requires the services of a technician ofconsiderable experience. For a technician of modest training, the properslicing of a section is approached on a trial and error basis, withconsequent expense of both time and effort. In surgical pathology,however, where a patient is frequently maintained under anesthetic onthe operating table pending the results of the microscopic examination,a time-consuming method of preparing the section cannot be tolerated.

One common solution to the rolling of the section concerns the use of asoft brush to assist the section as it leaves the knife. However, thistechnique requires a very delicate touch on the part of the technicianand is generally not at all satisfactory in routine use.

Accordingly, the principal object of the present invention is to providean improved method of slicing a thin section from a specimen.

An additional object of the invention to provide a device which willslice a section from a specimen without curling of the section.

Other objects and advantages of the invention will become apparent withreference to the following description and accompanying drawings inwhich:

FIGURE 1 is an isometric view of a microtome provided with means foraccomplishing the method of the present invention; 7

FIGURE 2 is a fragmentary elevational view of the specimen carrier ofthe microtome as viewed in the direction of the arrows 2-2 of FIGURE 1;and

FIGURES 3 and 4 are diagrammatic views showing the carrier of FIGURE 2,partially in section, as it moves the specimen into engagement with theknife of the microtome.

. Patented June 29, 1965 While it is recognized that the preparation ofthe sections, particularly tissue sections, generally involves adetailed procedure which includes such steps as the preparation of thespecimen, and the mounting of the specimen on the microtome, etc., thepresent invention is directed principally to that step in which thesection is sliced from the specimen. In accordance with the method ofthe invention (see FIGS. 3 and 4), a stream of gaseous fluid is directedtoward the section as it is formed so as to urge it against the face ofthe knife and thereby prevent its curling. Preferably, the gaseous fluidis directed across the surface of the specimen toward that edge of thespecimen which is the first to be contacted by the knife so that thestream of fluid will engage each portion of the section immediately uponits being formed, the section suitable results. When the knife isslicing the section from the specimen, therefore, the fluid will flowacross the outer face of the knife and will flatten the section againstthe face of the knife.

Also, it is found preferable to use a fluid below ambient temperature,especially when the specimen is frozen, and air from the cold well of acryostat has been found to be satisfactory for this purpose.

The device provided for carrying out the above-method is illustratedgenerally in FIGURE 1 and comprises a microtome 11 which includes agenerally rectangular base 13, on the rearward portion of which iscarried a box-like housing 15 having an elongated vertically disposedopening 17 in its forward wall through which a specimen carrier 19projects outwardly. The carrier is connected-to an operating mechanism(not shown) enclosed by the housing 15 which raises and lowers thecarrier and advances it forwardly when a handle 21, rotatably mounted ona side of the housing, is turned manually.

The carrier 19 comprises a generally cylindrical shaft 23 bored axiallyinto its forward face to provide a cavity 25 within which a specimen 27,embedded in the forward face of a rectangular paraffin block 29, iscarried. The block 29 is of such a size that the specimen projectsoutwardly of the cavity 25 in overhanging relation to a knife blade 31,hereinafter described, and is maintained within the cavity by a clampingplate 33 urged against the upper surface of the paraffin block 29 by anadjustable screw 35.

A knife support 37 is carried in a guideway 39 on the forward portion ofthe base 13 so as to be movable in the guideway to an out of the wayposition as, for example, when the knife blade 31 is to be replaced orcleaned. The blade 31 is carried at the upper end of the support 37 andis secured in place by set screws 41 which permit the blade -to beadjusted to various angles relative to the vertical as the occasion maydemand.

In order to carry out the method of the present invention, a nozzle 43is secured to the upper surface of the carrier shaft 23 by means of aclip 45, and is connected by a flexible hose 47 to a supply of gaseousfluid as, for example, a compressor in communication with the cold wellof a cryostat. The nozzle 43 is positioned so that it will direct a jetof fluid toward the face of the specimen at an angle of approximately 45degrees and, to ensure that its disposition will remain relativelyfixed, preferably includes a neck 49 formed of a flexible metal tubing.

As can be seen best in FIGURES 3 and 4, the fluid is directed toward thesurface of the specimen and, as the carrier is lowered so as to bringthe specimen into engagement with the knife blade 31, is deflected bythe specimen and flows downwardly along the forward face of the blade.As the section is being formed (FIG. 4), the flow of fluid urges thesection against the face of the blade and prevents the section fromcurling.

While the preferred form of the device for effecting the method has beenshown in the form of a microtome having a nozzle 43 mounted on thecarrier so as to travel with the carrier as it is raised and lowered, itshould be apparent that the method could be effected by mounting thenozzle on other portions of the microtome such as, for example, on theknife support 37. In the latter instance, of course, the nozzle wouldremain stationary during the operation of the device.

While various features of the invention have been shown and described,it should be apparent that various modifications may be made thereinwithout departing from the scope of the invention as set forth in thefollowing claims.

What is claimed is:

1. The method of providing a thin section of a specimen for use inmicroscopic examination, which method includes the step of slicing agenerally planar uniform thin section from a surface of the specimen bymeans of a knife while directing a stream of gaseous fluid toward thatedge of the specimen which is the first to be contacted by the knife soas to urge the section against the face of the knife as the section isbeing formed and thereby minimize curling thereof.

2. The method of providing a thin section of a specimen for use inmicroscopic examination, which method includes the step of slicing thesection from a surface of the specimen by means of a knife whiledirecting a stream of gaseous fluid having a temperature less thanambient toward that edge of the specimen which is the first to becontacted by the knife, said fluid being directed at an angle acute tothe surfaceof the specimen and in a direction which will urge thesection against the face of the knife as the section is being formed soas to thereby minimize curling thereof.

3. The method of providing a thin section of a specimen for use inmicroscopic examination, which method includes the step of slicing thesection from a surface of the specimen by means of a knife whiledirecting a stream of gaseous fluid having a temperature less thanambient toward that edge of the specimen which is the first to becontacted by the knife, said fluid being directed at an angle ofapproximately 45 degrees to the surface of the specimen in a directionwhich will urge the section against the face of the knife as the sectionis being formed so as to thereby minimize curling thereof.

4. In combination, a microtome including a specimen carrier and a knifeadjacent said carrier adapted to slice sections from the surface of thespecimen incident to predetermined relative reciprocal movement betweensaid carrier and knife, fluid-dispensing means connected to a source ofgaseous fluid under pressure, and means for mounting saidfluid-dispensing means so as to cause it to direct a stream of gaseousfluid toward that edge of the specimen which is the first to becontacted by the knife so as to cause the stream to flow over thesection and urge the section against the face of the knife as thesection is being formed, thereby overcoming the tendency of the sectionto curl.

5. In combination, a microtome including a specimen carrier and a knifeadjacent said carrier adapted to slice sections from the surface of thespecimen carried thereby incident to predetermined relative movementbetween said carrier and knife, fluid-dispensing means, means formounting said fluid dispensing means so as to direct a stream of gaseousfluid toward that edge of the specimen which is the first to becontacted by the knife, said fluid being directed by saidfluid-dispensing means at an angle acute to the surface of the specimenand in a direction which will urge the section against the face of theknife while the section is being formed to thereby minimize curlingthereof, and means connecting said nozzle to a supply of gaseous fluidhaving a temperature less than ambient.

6. In combination, a microtome including a specimen carrier and a knifeadjacent said carrier adapted to slice sections from the surface of thespecimen carried thereby incident to predetermined relative movementbetween said carrier and knife, a fluid-dispensing nozzle, means formounting said nozzle so as to direct a stream of gaseous fluid to 'ardthat edge of the surface of the specimen which is the first to becontacted by the knife, said fluid being directed at an angle ofapproximately 45 degrees to the surface of the specimen and in adirection which will urge the section against the face of the knifewhile the section is being formed, and means connecting said nozzle to asupply of air having a temperature less than ambient.

7. In combination, a microtome including a specimen carrier and a knifeadjacent said carrier adapted to slice sections from the surface of thespecimen when said carrier is moved relative to the edge of said knife,a fluiddispensing nozzle, means for mounting said nozzle on said carrierso as to direct a stream of fluid dispensed therefrom toward that edgeof the surface of the specimen which is the first to be contacted by theknife, said fluid thereby flowing across the face of the specimen towardsaid edge while said section is being formed, and means connecting saidnozzle to a supply of air under a pressure greater than atmospheric andof a temperature less-than ambient.

References Cited by the Examiner UNITED STATES PATENTS 1,648,938 11/27Dietrick 83169 2,061,581 11/36 Lippincott 8250 2,288,709 7/42 Hood146241 2,662,445 12/53 Jacoby 83915.5

ANDREW R. JUHASZ, Primary Examiner.

CARL W. TOMLIN, Examiner.

1. THE METHOD OF PROVIDING A THIN SECTION OF A SPECIMEN FOR USE INMICROSCOPIC EXAMINATION, WHICH METHOD INCLUDES THE STEP OF SLICING AGENERALLY PLANAR UNIFORM THIN SECTION FROM A SURFACE OF THE SPECIMEN BYMEANS OF A KNIFE WHILE DIRECTING A STREAM OF GENEOUS FLUID TOWARD THATEDGE OF THE SPECIMEN WHICH IS THE FIRST TO BE CONTACTED BY THE KNIFE SOAS TO URGE THE SECTION AGAINST THE FACE OF THE KNIFE SO AS THE SECTIONIN BEING FORMED AND THEREBY MINIMIZE CURLING THEREOF.